Extrusion tool

ABSTRACT

Plunger means for use in connection with an extrusion tool or the like comprises a displaceable auxiliary plunger portion longitudinally slidable along a recessed portion of the main plunger and normally biased to a first position wherein its first end extends forwardly of the first end or front end of the main plunger. When suitably contacted, the auxiliary plunger may be displaced rearwardly so that its front end is generally coincident with the front end of the main plunger. The resulting self-adjusting plunger assembly thus provides means for extruding differently sized connectors through a particularly sized orifice in an extrusion tool or the like. In operation, the auxiliary plunger portion precedes the main plunger into the extruding orifice when used in connection with the smaller connector, thereby selectively restricting the size of the orifice to that commensurate with the smaller connector. The larger sized connector will displace the auxiliary plunger portion rearwardly when contacted thereby so that both the main and auxiliary plunger portions operate to advance the connector through the extruding orifice. Biasing means which may comprise a compression spring or the like is provided to return the auxiliary plunger portion to its initial position after being displaced rearwardly along the main plunger recessed portion.

iJnited States Patent 191 Eppler Apr. 15, I975 EXTRUSION TOOL [75]Inventor: Daniel Eppler, Toms River, NJ.

[73] Assignee: Thomas & Betts Corporation,

Elizabeth, NJ.

22 Filed: June 14,1974

21 Appl.No.:479,431

[52] US. Cl. 72/259; 29/203 D; 29/628; 72/273 [51] Int. Cl. B21c 23/00[58] Field of Search 72/259, 273, DIG. 1; 425/517; 29/628, 630 A, 517,520, DIG. 47, 203 D [56] References Cited UNITED STATES PATENTS2,925,176 2/1960 Wyngaert 72/273 Primary Examiner-C. W. Lanham AssistantExaminer-Robert M. Rogers Attorney, Agent, or FirmDavid Teschner; JesseWoldman [57] ABSTRACT Plunger means for use in connection with anextrusion tool or the like comprises a displaceable auxiliary plungerportion longitudinally slidable along a recessed portion of the mainplunger and normally biased to a first position wherein its first endextends forwardly of the first end or front end of the main plunger.When suitably contacted, the auxiliary plunger may be displacedrearwardly so that its front end is generally coincident with the frontend of the main plunger. The resulting self-adjusting plunger assemblythus provides means for extruding differently sized connectors through aparticularly sized orifice in an extrusion tool or the like. Inoperation, the auxiliary plunger portion precedes the main plunger intothe extruding orifice when used in connection with the smallerconnector, thereby selectively restricting the size of the orifice tothat commensurate with the smaller connector. The larger sized connectorwill displace the auxiliary plunger portion rearwardly when contactedthereby so that both the main and auxiliary plunger portions operate toadvance the connector through the extruding orifice. Biasing means whichmay comprise a compression spring or the like is provided to return theauxiliary plunger portion to its initial position after being displacedrearwardly along the main plunger recessed portion.

14 Claims, 9 Drawing Figures '1 EXTRUSION TOOL BACKGROUND OF THEINVENTION l. Field of the Invention The invention isdirected to thefield of plunger means for extrusion tools, or the like.

2. Description of the Prior Art In US. Pat. No. 3,674,592, issued July4, 1972 to D. 0

Eppler and assigned to the assignee of the instant invention, there isshown an extrusion tool having a plunger, the end of which is bifurcatedto provide a slight variation in the size of the plunger upon entranceinto a tapered extrusion orifice. This feature permits the plunger tofollow a connector through the restrictively tapered orifice of theextrusion tool sufficiently to eject the connector from the exit end ofthe orifice while substantially filling the tapered orifice during theextrusion operation. The extrusion orifice, however, is designed toaccept a connector having a fixed dimension and, accordingly,restrictively limits the use of the tool in applications where aplurality of connector sizes are to be employed. In US. Pat. No.3,614,885, issued Oct. 26, 1971 to the same D. Eppler and assigned tothe assignee of the instant invention, there is disclosed a plungerarrangement comprising coaxially arranged outer and inner members, theinner member being telescopingly movable within the outer member and sopositioned as to provide a pocket or recess therebetween for accepting aportion of the connector therein as the connector is extruded throughthe extrusion orifice of the extrusion tool. The extrusion orifice ofthis tool is similarly dimensioned to accept only a single sizeconnector and the versatility and convenience of the tool is thereforelimited in essentially the same way as the first described device.Consequently, where the user is required to apply differently sizedconnectors in a particular application, it is necessary to haveavailable a plurality of tools, each provided with a specifically de'signed extrusion orifice, an arrangement which is generally quitecostly, cumbersome, and inconvenient in practice.

SUMMARY OF THE INVENTION The invention overcomes the difficulties andlimitations noted above with respect to prior art devices by providing acomposite plunger arrangement operative in an extrusion tool or the liketo permit the use of a single tool in conjunction with differently sizedconnectors in a manner more convenient, versatile, and economical thanwith such prior art devices. The plunger means comprises a first or mainplunger portion having a first end provided with a recessed portionadjacent which is disposed a second or auxiliary plunger portionlongitudinally slidable along the recessed portion and normally biasedtowards a first position in which the front end of the auxiliary orsecond plunger portion extends forwardly of the front end of the main orfirst plunger portionLThe auxiliary plunger portion may be rearwardlydisplaced longitudinally so that its front end is substantiallycoincident with the front end of thefirst or main plunger portion toprovide an essentially confor a connector having a transverse dimensionessentially equal to the corresponding transverse dimension of the mainplunger portion alone where the extruding orifice has a transversedimension essentially equal to the combined dimensions of both the mainplunger portion and the auxiliary plunger portion. In the other case,the second or auxiliary plunger portion is displaced rearwardly uponcontacting a connector having a transverse dimension essentially equalto the corre sponding combined transverse dimensions of both the mainand auxiliary plunger portion front ends and assumes a positionessentially coincident with the front end of the main plunger portion sothat the front ends of both the main and auxiliary plunger portionscooperate to advance the connector through the extruding orifice. It istherefore an object of this invention to provide improved plunger meansfor an extrusion tool or the like.

It is a further object of this invention to provide a self-adjustingplunger means for an extrusion tool or the like.

It is yet a further object of this invention to provide plunger means soconstructed as to permit the extrusion of differently sized connectorsthrough a given orifice of an extrusion tool or the like.

It is still another object of this invention to provide a segmentedplunger means for an extrusion tool or the like wherein the size of thefront working surface of the plunger means is selectively regulated bythe size of the connector to be extruded through the orifice of theextrusion tool.

It is yet another object of this invention to provide a plunger meanshaving a biased auxiliary plunger portion slidably displaceable on amain plunger portion for use in connection with differently sizedconnectors extrudable through a given orifice of an extrusion tool orthe like.

Other objects and features will be pointed out in the followingdescription and claims and illustrated in the accompanying drawingswhich disclose by way of example the principle of the invention and thebest modes contemplated for carrying it out.

BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings FIG. 1 is a sideelevational view, partly cut away and partly in section, of an extrusiontool employing an improved plunger means constructed in accordance withthe concepts of the invention.

FIG. 2 is a fragmentary side elevational view, in section, showing thedetails of a plunger means constructed in accordance with the conceptsof the invention.

FIG. 3 is a fragmentary side elevational view, in section, showing theplunger means of FIG. 2 selectively advanced into the orifice of anextrusion tool.

FIG. 4 is a fragmentary side elevational view, in section, similar toFIG. 2, showing the initial relative positions of the plunger means ofFIG. 2 and a given connector prior to extrusion.

FIG. 5 is a fragmentary side elevational view, partly cut away andpartly in section, showing the elements of FIG. 4 in an advanced stateof operation.

FIG. 6 is a fragmentary top plan view, partly cut away and partly insection, of the plunger means of the device of FIG. 2.

FIG. 7 is a front elevational view, in section, taken along the line 7-7of FIG. 6.

FIG. 8 is a front elevational view, in section, similar to FIG. 7, butshowing a further embodiment of plunger means constructed in accordancewith the concepts of the invention.

FIG. 9 is a fragmentary top plan view, in section, of yet anotherembodiment of plunger means constructed in accordance with the conceptsof the invention.

Similar elements are given similar reference characters in each of therespective drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to FIGS. 1, 2, 3,4, 5, 6, and 7 there is shown an extrusion tool 20 including a plungermeans 22 constructed in accordance with the concepts of the invention.The plunger means 22 is affixed to a support 24 operatively coupled to ahandle 26 pivotably mounted to a housing 28 having a nose portion 30comprising an extrusion orifice arranged to selectively deform aconnector advanced therethrough. A return spring 32 provides a biasingforce against the plunger support 24 to maintain the plunger means 22 ina retracted position prior to operation of the handle 26. It will ofcourse be appreciated by the those skilled in the art that although amanually operated tool is shown, the particular means employed toadvance the plunger means 22 forms no part of the invention and mayinclude pneumatically or hydraulically operated devices cooperative withthe plunger means 22. As best seen in the enlarged view of FIG. 2, theplunger means 22 comprises a first plunger portion 34 having a first end36 and a recessed portion 38 extending longitudinally rearwardly fromthe first end 36 and terminating in an upstanding surface 40. Extendingrearwardly from the upstanding surface 40 is a chamber 42 providing aseat for one end of a biasing means such as a compression spring 44.Slidably mounted on the first plunger portion 34 and moveable along therecessed portion 38 is a second plunger portion 46 having a first end 48and a sec ond end 50. A chamber 52, similar to chamber 42, extendsforwardly from the second end 50 of the second plunger portion 46towards its first end 48 to provide a seat for the other end of thecompression spring 44. The first plunger portion 34 is notched as at 54to provide a bifurcated arrangement employable in a manner which will bedescribed in greater detail hereafter. As best seen in FIG. 7, thesecond plunger portion 46 is provided with a generally planar surface 56slidable on a planar surface 58 defining the base of the recessedportion 38. As further illustrated in FIG. 7, the first and secondplunger means 34 and 46 respectively, have substantially rectangularcross sections of substantially equal transverse dimension. Accordingly,the sides of each of the first and second plunger portions may beclosely confined within a suitable bore extending lengthwise of thehousing 28 to provide at least a partial guide therefore. In a furtherembodiment, as illustrated for example in FIG. 8, a first plungerportion 60 may be provided with rib means 62 engaged withincomplementary slot means 64 in a second plunger portion 66 which,accordingly, is effectively guided by the ribs 62 between a firstposition wherein the first end 48 of the second plunger portion 46 isdisposed generally forwardly of the first end 36 of the first plungerportion 34 (FIG. 2) and a second position wherein the first end 48 ofthe second plunger portion 46 is generally coincident with the first end36 of the first plunger portion 34 (FIG. 5). The first ends 36 and 48,respectively, of the first plunger portion 34 and the second plungerportion 46 each terminate in a generally planar end surface adapted toprovide a generally uniform pressure against a connector such as 68 (SeeFIG. 2) positioned adjacent thereto for extrusion through a taperedorifice 70 extending axially through the nose portion 30 of the tool 20.It will of course be clear that the generally rectangular configurationof both the first and second plunger portions 34 and 46, respectively,may be modified, for example, by providing convex or concave side walls(not shown) slidable along complimentarily formed surfaces defining theinner walls of the housing 28 of tool 20, where necessary or desirable.The side walls of each of the first and second plunger portions 34 and46 adjacent their first ends 36 and 48 may be suitably tapered as shownat 72 and 74 in FIG. 6 to more closely follow the tapered contour of theadjacent sidewalls of the extrusion orifice 70. Operation of the plungermeans 22 when employed with a connector 68 having a transverse dimensiond slightly less than the opening between the surface 56 of the secondplunger portion 46 and the lower edge of the first plunger portion 34,as viewed in FIG. 2, may be more fully appreciated by referencespecifically to FIGS. 2 and 3. As illustrated in FIG. 2, the connector68 is positioned adjacent the nose portion orifice 70 by insertion, forexample, through an opening 78 in the tool housing 28. The mechanics ofsuch a feed arrangement have been disclosed in US. Pat. No. 3,674,392referred to hereinabove and, accordingly, will not be repeated here. Asfurther illustrated in FIG. 2, the plunger means 22 is shown in itsnormally retracted position, which, incidentally, provides anunobstructed passageway from the opening 78 into the interior of thetool 20 adjacent the first and second plunger portions 34 and 46. Theplunger 22 is now advanced by movement of the handle 26 towards thehousing 28 of the tool 20, causing a for- 1 ward displacement of theplunger means 22 to a position essentially as shown in FIG. 3. Asillustrated therein, the forwardly extending section of the secondplunger portion 46 overlies the top surface 76 of the connector 68during the forward motion of the plunger means 22. Accordingly, as thesecond plunger portion 46, the first plunger portion 34, and theconnector 68 are advanced into the orifice 70, the second plungerportion 46 is maintained in its extended position by the compressionspring 44 and continues to overlie theconnector 68 throughout theforward motion of the plunger means 22. As the plunger means 22 isfurther advanced, the connector 68 is subjected to opposing forcesexerted by the selectively tapered sidewalls of the orifice 70 one ofwhich is indicated at 78. The surface 78 tends to urge the connector 68towards the adjacent surface 56 of the second plunger portion 46 whichprevents further transverse movement of the connector 68 so that as thefirst plunger portion 34 continues to advance the connector 68 throughthe orifice 70, the connector 68 is extruded through the exit end of theorifice 70 essentially as illustrated in FIG. 3. The second plungerportion surface 56 thus serves to provide an auxiliary support surfacefor the connector 68 to insure that the connector is confined within thespace available between the surface 56 of the second plunger portion 46and the tapered sidewall 78 of the extruding orifice 70. Thus, althoughthe orifice 70 has a substantially larger transverse dimension than theconnector 68, the second plunger portion 46 operates to selectivelyreduce the available opening to .insure proper extrusion of theconnector 68 therethrough. As further illustrated in FIG. 3, a pair ofconductors 80 and 82 each having a bared end 84, 86, respectively, maybe connected to one another. by the insertion of the bared ends 84 and86 into a suitable conductor receiving orifice in the connector 68 priorto the extrusion of the connector 68 through the orifice 70. As theconnector 68 is advance through the orifice 70, its convergingly taperedsurfaces tend to selectively close each of the conductor receivingopenings about the conductors 80 and 82 to provide a secure connectiontherebetween. It will be further noted that the bifurcated structure ofthe first plunger portion 34 permits it to advance freely into theorifice 70 to insure that the connector 68is fully extruded through theexit end of the orifice 70. In FIGS. 4 and 5, operation of theplungermeans 22'for extruding a connector 82 through the extrudingorifice 70 is illustrated in greater detail. In this case, the connector82 has a transverse dimension d generally equal to the correspondingcombined transverse dimensions of'both the first plunger portion 34 andthe second plunger portion 46. Accordingly, as the plungerm eans 22 isadvanced forwardly, the front end 48 of the second plunger portion 46 iscaused to abut the adjacent surface of the connector 82 indicatedgenerally at 83, whereby the second plunger portion 46 is longitudinallydisplaced rearwardly, compressing the biasing spring 44, and assuming aposition relative to the front end 36 of the first plunger portion 34essentially'as shown in FIG. 5. The first end 48 of the second plungerportion 46 and the first end 36 of the first plunger portion 34 thuspresent a generally contiguous surface bearing against the connector 82during the extrusion operation. The upstanding surface 40 disposed atthe terminating end of the recessed portion 38 of the first plungerportion 34 is arranged to provide an abutment to restrict furtherrearward movement of the second plunger portion 46 during the extrusionoperation. The end surfaces of each of the first and second plungerportions 34 and 46, respectively, although shown and describedhereinabove as generally planar may be suitably configured in a varietyof other shapes which may include convex and concave portions arrangedto cooperate with suitably formed complementary surfaces on connectorsselectively designed for use in connection therewith. Additionally,various indicia may be provided as raised or recessed elements at thefront surfaces of the first and second plunger portions to code or markthe connectors as they are urged through the restrictive nose orifice70. Although not illustrated, it will be readily apparent to thoseskilled in the art that the second plunger portion 46 may be bifurcatedin a manner similar to that illustrated with respect to the firstplunger portion 34 to permit an increased taper to be employed in thenose portion orifice 70, where necessary or desirable.

Referring now to FIG. 9 there is shown a further embodiment of a plungermeans 84 constructed in accordance with the concepts of the invention.As illustrated therein, the plunger means 84 comprises a first plungerportion 86 flanked by a pair of second plunger portions 88 and 90respectively, each essentially duplicative of element 46 illustrated anddescribed in detail hereinabove, and slidable along recessed portions 91and 93 disposed on opposite sides of the first plunger portion 86. Eachof the second plunger portions 88 and is resiliently coupled to the mainbody of the plunger means 84 by biasing means comprising compressionsprings 92 and 94 similar to the compression spring 44 of the embodimentillustrated in FIG. 2.-This arrangement provides additional versatilityin that three differently sized connectors may be extruded through thesame extruding orifice of the extrusion tool in a manner essentiallysimilar to that described above with respect to the embodimentillustrated in FIGS. 2 through 7. By way of example, the solid outlineindicated by the reference numberal 96 defines the contour of thesmallest of the three differently sized connectors which may be extrudedthrough the nose portion orifice indicated as 98 in FIG. 9. In suchcasefeach of the second plunger portions 88 and 90 operate to reduce thetransverse dimension of the orifice 98 while the first plunger portion86 operates to extrude the connector 96 between the second plungerportions 88 and 90 and the tapered inner surfaces 110 and 112 of theorifice 98. A second connector having a contour including the solidoutline indicated by numeral 96 but further including a portion 100indicated by the dotted outline adjacent the second plunger portion 88may be extruded through the orifice 98 in a manner similar to thatdescribed with respect to the connector 82 shown in FIGS. 4 and 5. Inthis case, the second plunger portion 90 provides the additional closurenecessary to contain the connector including portions 96 and 100properly within the orifice 98 for extrusion therethrough. When used inconjunction with a connector having a contour defined generally by thesolid outline 96 together with the dotted outlines 100 and 102, theembodiment illustrated in FIG. 9 functions in a manner similar to thatdescribed above with respect to the arrangement shown in FIGS. 4 and 5,except that both second plunger portions 88 and 90 are displacedlongitudinally rearwardly to provide a generally contiguous surfacecomprising the front surfaces of both second plunger portions 88 and 90,and the first plunger portion 86. Accordingly, as the plunger means 84is advanced forwardly towards the nose portion orifice 98, the front endsurfaces of all three elements function cooperatively to urge theconnector through the orifice 98. It will also be clear to those skilledin the art that each of the second plunger portions 88 and 90 may becooperatively guided along the adjacent surfaces of the first plungerportion 86 by the employment of complementary ribs and slots such as theelements 62 and 64 illustrated in' FIG. 8. A slot 108 bifurcates thefirst plunger portion 86 to pennit a variation in the transversedimension thereof in a manner similar to that described above withrespect to the element 34, whereby the second plunger portions 88 and 90may more closely follow the inner tapered surfaces of the orifice 98,which are indicated generally at 110 and 112 in FIG. 9.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

l. Plunger means for use in connection with an extrusion tool or thelike comprising: a generally elongate first plunger portion having afirst end and a recessed portion extending rearwardly from said plungerportion first end; a second plunger portion slidable generallylongitudinally on said first plunger portion recessed portion and havinga first end and a second end; and biasing means cooperative with saidfirst plunger portion and said second plunger portion for biasing saidsecond plunger portion first end selectively forward of said firstplunger portion first end. I

2. Plunger means as defined in claim 1 wherein said biasing meanscomprises spring means.

3. Plunger means as defined in claim 2 wherein said spring meanscomprises a compression spring and said second plunger portion has alongitudinally extending orifice, said compression spring beingselectively engageable within said second plunger portion orifice.

4. Plunger means as defined in claim 1, said second plunger portionbeing selectively movable to a second position wherein said first endthereof is generally coincident with said first plunger portion firstend.

5. Plunger means as defined in claim 1 further comprising meansforguiding said second plunger portion along said first plunger portionrecessed portion.

6. Plunger means as defined in claim 5 wherein said first plungerportion comprises rib means extending longitudinally along said recessedportion, and said second plunger portion comprises slot means engagingsaid rib means to guide said second plunger portion along said firstplunger portion recessed portion.

7. Plunger means as defined in claim 1 wherein said biasing meanscomprises a compression spring, and said first plunger portion has alongitudinally extending orifice communicating with said recessedportion, said compression spring being selectively engageable withinsaid first plunger portion orifice.

8. Plunger means as defined in claim 1 wherein said first and saidsecond plunger portions are of substan- 8 tially equal width.

9. Plunger means as defined in claim 1 wherein said first and secondplunger portions have correspondingly selectively tapered sidesgenerally adjacent said first ends thereof.

l0. Plunger means as defined in claim 1 wherein said first plungerportion recessed portion comprises an upstanding surface remote fromsaid first plunger portion first end for limiting the rearward travel ofsaid second plunger portion.

11. Plunger means as defined in claim 10 wherein said first plungerportion recessed portion comprises a generally planar surface, saidsecond plunger portion being slidable along said recessed portion planarsur face. i

12. Plunger means as defined in claim 11 wherein saidsecond plungerportion comprises a generally planar surface, said second plungerportion planar surface being slidable along said recessed portion planarsurface.

l3. Plunger means as defined in claim 1 wherein said first plungerportion and said second plunger portion each have a substantiallyrectangular configuration in cross section.

14. Plunger means as defined in claim 1 wherein said first plungerportion first end terminates in a first generally planar surface, andsaid second plunger portion first end terminates in a second generallyplanar surface, said second plunger portion being movable rearwardly sothat said second planar surface is generally coincident with said firstplaner surface to provide a generally contiguous surface thereat.

1. Plunger means for use in connection with an extrusion tool or thelike comprising: a generally elongate first plunger portion having afirst end and a recessed portion extending rearwardly from said plungerportion first end; a second plunger portion slidable generallylongitudinally on said first plunger portion recessed portion and havinga first end and a second end; and biasing means cooperative with saidfirst plunger portion and said second plunger portion for biasing saidsecond plunger portion first end selectively forward of said firstplunger portion first end.
 2. Plunger means as defined in claim 1wherein said biasing means comprises spring means.
 3. Plunger means asdefined in claim 2 wherein said spring means comprises a compressionspring and said second plunger portion has a longitudinally extendingorifice, said compression spring being selectively engageable withinsaid second plunger portion orifice.
 4. Plunger means as defined inclaim 1, said second plunger portion being selectively movable to asecond position wherein said first end thereof is generally coincidentwith said first plunger portion first end.
 5. Plunger means as definedin claim 1 further comprising means for guiding said second plungerportion along said first plunger portion recessed portion.
 6. Plungermeans as defined in claim 5 wherein said first plunger portion comprisesrib means extending longitudinally along said recessed portion, and saidsecond plunger portion comprises slot means engaging said rib means toguide said second plunger portion along said first plunger portionrecessed portion.
 7. Plunger means as defined in claim 1 wherein saidbiasing means comprises a compression spring, and said first plungerportion has a longitudinally extending orifice communicatinG with saidrecessed portion, said compression spring being selectively engageablewithin said first plunger portion orifice.
 8. Plunger means as definedin claim 1 wherein said first and said second plunger portions are ofsubstantially equal width.
 9. Plunger means as defined in claim 1wherein said first and second plunger portions have correspondinglyselectively tapered sides generally adjacent said first ends thereof.10. Plunger means as defined in claim 1 wherein said first plungerportion recessed portion comprises an upstanding surface remote fromsaid first plunger portion first end for limiting the rearward travel ofsaid second plunger portion.
 11. Plunger means as defined in claim 10wherein said first plunger portion recessed portion comprises agenerally planar surface, said second plunger portion being slidablealong said recessed portion planar surface.
 12. Plunger means as definedin claim 11 wherein said second plunger portion comprises a generallyplanar surface, said second plunger portion planar surface beingslidable along said recessed portion planar surface.
 13. Plunger meansas defined in claim 1 wherein said first plunger portion and said secondplunger portion each have a substantially rectangular configuration incross section.
 14. Plunger means as defined in claim 1 wherein saidfirst plunger portion first end terminates in a first generally planarsurface, and said second plunger portion first end terminates in asecond generally planar surface, said second plunger portion beingmovable rearwardly so that said second planar surface is generallycoincident with said first planer surface to provide a generallycontiguous surface thereat.